Tandem Air Propellers - II
A 1939 NACA technical report on tandem air propellers, published by the National Advisory Committee for Aeronautics and preserved through NASA's Technical Reports Server, written for aircraft engineers. Its pictures pair a design chart plotting efficiency against thrust and power coefficients for three-blade right and left-hand tandem propellers with photographs of the propeller hardware in a wind tunnel. A designer could take from them the crisp engineering line-graph style with its stepped grid and labelled curves, plus the sculptural overlap of paired blades seen head-on.
